Sawdust cultivation of Lentinula edodes has been increasing in Korea. Fourteen strains were used to develop the best varieties of L. edodes, and hybridization was carried out by monohybrid cross. The number of hybridized strains was 1,638 among 3,100 combinations. They were cultivated on sawdust medium, and fruiting bodies were formed in 364 strains. Among them, 65 strains were selected as superior candidate strains based on the shape and size of the fruiting bodies. Forty strains formed fruiting bodies without lamellae structure. The shape of the stipe was cylindrical (255 strains), thick to lower part (15 strains), and thick to upper part (94 strains). By the combinations of 2462 n1-10 and 3420 n1-10, 2462 n1, 2462 n2, 2462 n10, and 3420 n3 were selected as excellent monokaryotic strains. These strains were considered to be superior monokaryotic strains that could be used for hybrid breeding.